Chemical Changes in Nagpur Mandarin (Citrus Reticulata Blanco) as Influenced by Storage Temperature and Duration

Introduction

Mandarin orange is an important citrus fruit widely consumed because of its nutritional and commercial value. It is an evergreen fruit tree belonging to the family Rutaceae and produces attractive orange-coloured fruits. Freshly harvested fruits and vegetables remain physiologically active and continue to respire after harvest, which contributes to progressive changes in quality during storage (Snowdown, 1988). Mandarin orange is a non-climacteric and highly perishable fruit; therefore, its storage and transportation for extended periods can result in considerable quality deterioration. During post-harvest handling, both external and internal quality attributes, including total soluble solids (TSS) and titratable acidity (TA), may change with storage. Inadequate adoption of improved pre-and post-harvest technologies can further accelerate these changes. Post-harvest treatments are important for extending the shelf life and maintaining the quality of fruits (Deka, 2006, Patil et al., 2024, Patil et al., 2026) [1] . Post-harvest losses can be reduced by controlling transpiration, respiration, microbial infection, and deterioration of cellular membranes (Sahu, 2016). Therefore, appropriate post-harvest treatments and storage conditions are essential for slowing physiological deterioration, maintaining quality attributes, and extending the shelf life of mandarin orange

Materials and methods

The investigation was carried out in the Food Engineering Laboratory, Department of Agricultural Process Engineering, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola. Fresh Nagpur mandarin (Citrus Reticulata Blanco) fruits were obtained from the local market at the initial colour-break stage. Fruits free from visible injuries, diseases and physical defects, and having relatively uniform size, were selected for the study. The fruits were cleaned with water, surface-dried and subsequently subjected to storage under controlled temperature conditions of 5 ± 2 °C, 10 ± 1 °C, 15 ± 1 °C, along with an ambient control of 25-30 °C. The experiment was conducted using a factorial completely randomized design (FCRD) with three replications. The biochemical composition of the stored fruits was assessed through total soluble solids, titratable acidity, pH, total sugars and ascorbic acid content. Total soluble solids were measured using a digital refractometer following Jawandha et al. (2012). Titratable acidity was estimated by neutralization titration with sodium hydroxide according to Thakur et al. (2002) and Patil et al., (2024) [2] , while juice pH was determined using a calibrated digital pH meter following Palma et al. (2003). Total sugar content was estimated by the volumetric procedure of Lane and Eynon (1923), and ascorbic acid was quantified by the dye-titration method of Tillmans (1932).

Statistical analysis

During this study, a Factorial design under factorial Completely Randomized Design (FCRD) was used in the experiment. There were four treatments; each cultivar represents a treatment, and each treatment has three replications, and every replication has 30 fruits. The data was analyzed statistically through a 2-way Analysis of Variances (ANOVA). The differences among treatment means were analyzed using the LSD test at a 5% level of significance

Result and Discussion

Total soluble solid (TSS)

Total soluble solids (TSS) were determined using an ATAGO RX-5000 digital refractometer. An aliquot of freshly extracted juice was placed on the prism, and TSS was recorded and expressed as percentage (%). TSS increased during storage, indicating changes in fruit juice composition. The highest value was recorded in the control at 14 days (22.73 °Brix), followed by 5 °C (20.00 °Brix). The lowest TSS was recorded at 10 °C (15.27 °Brix) after 14 days (Table 1). Nagpur mandarin quality was evaluated at different temperatures. TSS increased over 14 days at 5 °C (8.37 to 20.00 °Brix), 10 °C (10.13 to 15.27 °Brix), and 15 °C (8.20 to 18.63 °Brix). In the control, it rose from 12.37 to 22.73 °Brix by day 7, then declined to 5.00 °Brix at day 14 (fig 1 . A)).

Titratable acidity was determined by titrating a diluted fruit juice aliquot with 0.1 N NaOH using phenolphthalein as an indicator. The endpoint was identified by the development of a persistent pink colour, and acidity was expressed as (%) (Patil et al., 2024) [2] . Titratable acidity decreased gradually during storage. The highest value was 1.61% in the control at day 0, while the lowest value was 1.47% at 5 °C and 10 °C after 14 days. Acidity decreased during storage due to organic acid utilization in respiration (Table1). Titratable acidity showed a gradual decreasing trend during storage. It decreased from 1.52% to 1.47% at 5 °C, 1.53% to 1.47% at 10 °C, 1.55% to 1.50% at 15 °C, and 1.61% to 1.55% in the control from 0 to 14 days.

Juice pH

Freshly extracted fruit juice was analysed for pH using a HANA 8520 pH meter after calibration at pH 7.0.

Ascorbic acid concentration was quantified by the 2,6-dichloroindophenol (DCPIP) titrimetric method. The clarified juice extract was titrated against standardized DCPIP using 4% oxalic acid as the extraction medium until a persistent faint-pink endpoint was observed.

Results were expressed as mg ascorbic acid per 100 mL of juice. Ascorbic acid decreased during storage, possibly due to oxidation. The highest initial content was recorded at 10 °C (54.93 mg/100 g), while the control recorded the lowest value at 14 days (47.95 mg/100 g). (Table 1). Ascorbic acid decreased slightly during storage at 5 °C,

Total sugar was determined by the Lane-Eynon titrimetric method using Fehling's solutions and methylene blue indicator. The fruit extract was hydrolysed, neutralized, and titrated with standardized sucrose solution under boiling conditions. Sugar content was calculated from the blank and sample titre values and expressed as percentage. Total sugar increased with storage duration at all temperatures, Total sugar increased with storage duration, possibly due to the conversion of complex carbohydrates into simpler sugars. The highest value was recorded at 10 °C (7.05%) after 14 days, followed by the control (6.76%) (Table 1). Total sugar content increased during storage, reaching the highest value of 7.05% at 10 °C after 14 days.

Conclusion

It is concluded that Storage temperature and duration significantly affected the quality and shelf life of Nagpur mandarin. Storage at 10 °C was most suitable for maintaining fruit quality and reducing chilling injury. Prolonged storage increased moisture loss and quality deterioration. Therefore, 10 °C storage is recommended for extending the shelf life and maintaining the marketable quality of Nagpur mandarin fruits.

References

1. Patil B, Gupta S, Shelke G, Patil N, Kalbande S, Khalid Alqahtani N, Sami R, Alkhudhayri D, Jalloun R, Helal M. Sustainable processing approach: influence of microwave power and foam thickness on drying kinetics and quality of foam-mat dried mandarin powder. Frontiers in Sustainable Food Systems. 2026;10:10.3389/fsufs.2026.1765188.
2. Patil BN, Gupta SV, Patil NB, Yewle N. Influence of microwave drying on quality parameters of foamed Nagpur Mandarin (Citrus reticulata) juice. Heliyon. 2024;10:e30449.
3. Aghaei F, Ramezanian A, Saharkhiz MJ, Golmakani MT, Rowshan V. Enhancement of bioactive compounds in "Valencia" orange peel waste during cold storage by melatonin and arginine treatments. Food Science & Nutrition. 2025;13:e70448.
4. Ahmad MS, Thakur KS, Siddiqui MW. Postharvest treatments for preserving quality of 'Kinnow' fruit under different storage conditions. Adv. Hort. Sci. 2013;27(4):1-7.
5. Altaf N, Khan AR, Hussain J. Fruit variability in Kinnow mandarin (Citrus reticulata). Pakistan Journal of Botany. 2008;40(2):599-604.
6. Bhardwaj RL, Nandal U. Effect of storage temperature on chemical and sensory evaluation of Kinnow mandarin juice blends. Journal of Food Processing & Technology. 2014;5(8):361.
7. Altaf N, Khan AR, Hussain J. Fruit variability in Kinnow mandarin (Citrus reticulata). Pakistan Journal of Botany. 2008;40(2):599-604.
8. Aruna K, Vimala V, Dhanalakshmi K, Vinodini R. chemical changes during storage of papaya fruit (Carica papaya L.). J. Food Sci. Technol. 1999;36(5):429-433.
9. Bhardwaj RL, Nandal U. Effect of storage temperature on chemical and sensory evaluation of Kinnow mandarin juice blends. Journal of Food Processing & Technology. 2014;5(8):361.
10. Bhatnagar P, Singh J, Jain MC, Singh B, Manmohan JR, Dashora LK. Studies on seasonal variations in developing fruits of Nagpur Mandarin (Citrus reticulata Blanco) under Jhalawar conditions. Asian Journal of Horticulture. 2012;7(2):263-265.
11. Chin MF, Tan SS, Tan ST, Tan CX. chemical properties and storage stability of cold-pressed orange juice. Food Chemistry International. 2025.
12. Fahim MA, Hassan MK, Akhther N, Howlader NC, Sarker S, Hossain MS, Sheikh MH, Rokon AH. Prolonging shelf life and preserving quality: A study on orange varieties under different storage conditions. Acta Horticulturae et Regiotecturae. 2025;28(2):89-98.
13. Kafkaletou M, Velliou A, Christopoulos MV, Ouzounidou G, Tsantili E. Impact of cold storage temperature and shelf life on ripening physiology, quality attributes, and nutritional value in apricots-Implication of cultivar. Plants. 2023;12(15):2875.
14. Kashyap K, Kashyap D, Nitin M, Ramchiary N, Banu S. Characterizing the nutrient composition, physiological maturity, and effect of cold storage in Khasi mandarin (Citrus reticulata Blanco). International Journal of Fruit Science. 2020;20(3):521540.
15. Ladaniya MS, Sonkar RK. Influence of temperature and fruit maturity on Nagpur mandarin (Citrus reticulata Blanco) in storage. Indian J. Agric. Sci. 1996;66:109-113.
16. Obenland D, Collin S, Mackey B, Sievert J, Arpaia ML. Storage temperature and time influences sensory quality of mandarins by altering soluble solids, acidity and aroma volatile. 2011. 17. composition. Postharvest Biology and Technology. 2011;59(2):187-193.
17. Puri C, Lamsal M, Acharya B. Effect of post-harvest treatment on quality and shelf life of mandarin orange in cold store. In S. Karki, P. R. Poudel, Y. K. Shrestha, S. P. Baral, S. Dhimal, S. Paudel, & S. Pandit (Eds.), Mandarin orange: History, science and technology in Nepal (p. 389). NHS & NCFD, Kathmandu; 2024.
18. Rapisarda P, Bellomo SE, Intelisano S. Storage temperature effects on blood orange fruit quality. Journal of Agricultural and Food Chemistry. 2001;49(7):3230-3235.
19. Rokaya PR, Baral DR, Gautam DM, Shrestha AK, Paudyal KP. Effect of altitude and maturity stages on quality attributes of mandarin (Citrus reticulata Blanco). Am. J Plant Sci. 2016;7:958.
20. Sokra I, Socheata C, Somaly S. Cold storage technologies for fresh fruits: impacts on shelf life and nutritional quality. Journal of Agriculture and Technology. 2026;2(1):66-71.
21. Somaly S, Lika R, Socheata C, Sokra I. Optimal storage temperature for fresh fruits, quality retention, and shelf-life extension. Journal of Agriculture and Technology. 2026;2(1):79-84.
22. Shravan R, Shere DM, Joshi Monali M. Study of chemical characteristics of sweet orange (Citrus sinensis) fruit. Journal of Pharmacognosy and Phytochemistry. 2018;7(6):1687-1689.
23. Tietel Z, Lewinsohn E, Fallik E, Porat R. Importance of storage temperatures in maintaining flavor and quality of mandarins. Postharvest Biology and Technology. 2012;64:175-182.